The invention concerns an operating unit for an electrophotographic printing or copying system. The operating unit has a graphical user interface with input and output fields, with whose help an operation of the electrophotographic printing or copying system occurs.
Known electrophotographic printing or copying systems comprise an operating unit via which the processing (execution) of print jobs, the operating mode of the printer, and parameters and set values are shown to operating personnel with the aid of a graphical user interface, whereby the operating personnel implement operator control actions via inputs. The set values concern in particular parameters of the printer or copier that operating personnel must adjust to implement different print jobs. For service and maintenance tasks that require access to internal control variables of the printer or copier, a special service and maintenance computer is connected with the printer or copier. The control variables are shown via a user interface of the service and maintenance computer, whereby at least one part of these control variables can be changed. In general, it is not expedient to allow the operating personnel access to set values and parameters of the printer or copier, in particular not when an impairment of the print quality or a damage of components of the printer is possible given a wrong setting. On the operating unit, the operating personnel are thus only allowed operating inputs for operation of the printer or copier that are necessary for processing of print jobs. The further adjustments are only possible via the maintenance computer.